Fractions
Comparing Fractions with Unlike Denominators
When Fractions
have
Different Denominators,
those Fractions
must first be changed to Fractions
with Like Denominators.
3
4
5
8
To change these Fractions
to Like Denominators,
first find the Least Common Denominator.
The Least Common Denominator
of 4 and 8
is 8.
3
4
8
÷
4
=
2
Divide the Least Common Denominator
of the Fractions
by the Denominator
of the first Fraction.
3
4
x
x
2
2
=
=
6
8
Then multiply
both the Numerator
and the Denominator
of the first Fraction
by that same number.
Do the same for the
of the second Fraction .
5
8
8
÷
8
=
1
5
8
x
x
1
1
=
=
5
8
With Like Denominators,
the two Fractions
can now be compared.
6
8
is greater than
5
8
therefore
3
4
is greater than
5
8
RULE
Comparing Fractions with Unlike Denominators
First find the Least Common Denominator.
Then change those Fractions to Fractions with Like Denominators.